Drum Load Monitoring

ABSTRACT

An assembly for monitoring load on a drum during an operation in a well with a well access line deployed from the drum. The assembly may include multiple line detection mechanisms for acquiring real-time information relative to dynamic characteristics of the lone over the course of the operation. The assembly also includes a processor for computing the real-time information in light of pre-stored information relative to physical characteristics of the line and the drum. As a result, real-time monitoring of a load on the drum may be achieved. Thus, the operation may be adjusted in real-time as necessary to avoid over-loading of the drum. Additionally, a drum load history may be recorded so as to better account for the true condition of the drum following successive operations.

FIELD

Embodiments described relate to drum assemblies for delivering a wellaccess line and downhole tools thereon to a well. Such well access linemay include wireline cables, slickline and others. Additionally, a drumassembly may include monitoring equipment and techniques directed atkeeping track of a load imparted on the drum in real-time during a givendownhole operation. Furthermore, a drum history keeping track of loadrelative to the drum over a number of successive operations may bemaintained.

BACKGROUND

Exploring, drilling and completing hydrocarbon and other wells aregenerally complicated, time consuming and ultimately very expensiveendeavors. As such, tremendous emphasis is often placed on well accessin the hydrocarbon recovery industry. That is, access to a well at anoilfield for monitoring its condition and maintaining its proper healthis of great importance in the industry. As described below, such accessto the well is generally provided by a well access line accommodated bya drum positioned at the oilfield.

During monitoring and maintaining of a well, a host of oilfieldequipment may be located at the oilfield near the well. As indicated,one such piece of equipment may be a drum assembly accommodating a wellaccess line. The well access line itself is generally a wireline cableor slickline configured to secure a well tool at a downhole end thereof.Alternatively, the drum may be a “reel” of coiled tubing line capable ofdelivering a fluid therethrough and to the well. In the case of coiledtubing, the line may be threaded through an injector arm and into thewell, whereas the more conventional wireline or slickline may be droppedinto the well from a mast over the well. Regardless, several thousandfeet of line may ultimately be deployed from the drum and delivered intothe well, thereby providing well access for a variety of well monitoringand maintenance procedures.

Unfortunately, the several thousand feet of line wrapped about the drumassembly tends to take its toll on the drum. That is, the drum may besubjected to the pressure or load of the line itself simply by havingthe line wrapped thereabout. Additionally, over the course of wellaccess operations as described above, tension on the line may increasethe load on the drum. This may particularly be the case when the drum isdirected by a winch to pull the line in an uphole direction, forexample, at the conclusion of an operation. In such circumstances, theline may face obstacles which impede the uphole movement thereof, suchas obstructions or bends in the well architecture. Regardless, when suchobstacles are presented, the load imparted on the drum through theincrease in tension on the line may be quite significant.

Drums for well access operations, such as wireline operations, aregenerally constructed to withstand significant amounts of load.Nevertheless, the cumulative effects of such high tension and resultinghigh load as noted above may lead to plastifying of the drum, which mayleave the drum ineffective for proper use in well access operations. Thedrum is particularly susceptible to plastifying of this nature at ajunction of its core, about which the line is wrapped, and the wall-likeflanges at the sides thereof, which help to retain the line in positionabout the core. Unfortunately, once rendered ineffective in this manner,the drum may be replaced at a cost that is often in excess of $80,000 ormore in today's dollars.

Furthermore, the frequency of drum replacement for well accessoperations has risen sharply in the last several years and is likely tocontinue rising. This is a result of the sophisticated wells which arebecoming more and more common. That is, in today's hydrocarbon recoveryindustry, deeper and deeper wells are regularly employed which require agreater amount of line for access. In some cases, the line may exceed30,000 feet or more. This naturally places a greater amount of load onthe drum from the outset, even before any of the line is deployed.Additionally, highly deviated and tortuous wells are becoming more andmore common. As a result, the tension of the line on the drum isincreased due to the added amount of friction and fluid resistance thataccompany wells of such complicated architecture. All in all, the lifeexpectancy of a conventional drum regularly employed in such hightension operations is significantly reduced.

Efforts have been made to minimize the load imparted on the drum duringa given well access operation. One such effort is to employ an expectedtension or load profile which is established in advance of theoperation. So, for example, in the case of a particularly tortuous well,retrieval of the line may proceed in a manner that accounts for atoolstring rounding a bend in the well or other predictable occurrencesthat may be accounted for by the profile. Thus, the parameters of theretrieval may be adjusted to account for the line pulling the toolstringequipment around the bend.

Unfortunately, many of the factors which lead to an increase in tensionon the line may not be built into an expected load profile. That is,much of what causes tension on the line is a matter of the ‘unexpected’.For example, the expected load profile would not account for unknownobstructions or unexpected changes in pressure that result indifferential sticking. Thus, advance warning is not always available.Furthermore, there remains an absence of real-time drum load monitoringto address this issue. This is due to mechanical interfacing challengespresented by the prospect of directly monitoring a load on a rotatingdrum. Additionally, in circumstances where the drum does make it throughthe operation in spite of concerns over potentially exceeded loadthresholds, other concerns remain. For example, due to the lack ofdirect drum load information, no reliable load history is preserved forthe drum. As a result, rather than risk a catastrophic event duringoperation, the drum is most likely discarded after a given number ofuses irrespective of its actual structural condition.

SUMMARY

An assembly for monitoring a load on a drum is provided. The assemblymay include a line monitoring mechanism that is coupled to a line thatis deployed from the drum. A processor having pre-loaded drum datastored thereon may be coupled to the line monitoring mechanism so as toallow for a running of drum load computations based on the drum data andthe line data.

A method of monitoring a load on a drum is provided. The drum may beconfigured to accommodate a line for access to a well. Drum informationindicative of physical characteristics of the drum may be stored on aprocessor and the line positioned within the well. Line informationindicative of physical characteristics of the line may be acquiredduring the positioning thereof within the well. Additionally, theprocessor may be employed to dynamically compute the load on the drumduring the positioning based on the available line and drum information.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an enlarged view of an embodiment of a drum load monitoringassembly taken from 1-1 of FIG. 2.

FIG. 2 is an overview of the drum load monitoring assembly of FIG. 1positioned at an oilfield for a well access line operation.

FIG. 3A is a schematic representation of an embodiment of a drum loadmonitoring assembly analyzing information inputs to establish drum load.

FIG. 3B is a flow-chart summarizing an embodiment of establishing drumload in real-time during a well access operation.

FIG. 4A is a chart depicting variation in a monitored load from thetension of a well access line that is directed at a drum over the courseof a well access operation.

FIGS. 4B and 4C are side views of the drum referenced in 4A revealingthe site specific pressure distribution imparted by the monitored load.

FIG. 5 is a chart depicting drum history in terms of total load over thecourse of successive well access operations.

DETAILED DESCRIPTION

Embodiments are described with reference to certain drums and wellaccess operations. For example, an embodiment of a particular wirelinelogging operation is depicted and described throughout. However, avariety of different types of well access operations may employembodiments of drum load monitoring tools and techniques as detailedherein. Regardless, embodiments described herein include line detectionmechanisms for detecting line length and tension, along with a processorcoupled to the mechanisms that also has pre-stored drum data thereon.

Referring now to FIG. 1, an embodiment of a drum load monitoringassembly 100 is shown. FIG. 1 is an enlarged view of the assembly 100taken from 2-2 of FIG. 2 which shows a larger overview of the assembly100 positioned at an oilfield 297. In the embodiment shown, the assembly100 is positioned for wireline operations. More specifically, a wellaccess line 110 in the form of a wireline is deployed into a well 180with a logging tool 177 secured thereto for logging operations. However,in other embodiments a variety of other downhole operations may proceedas noted above.

The above noted line 110 is deployed from a drum 130 of deploymentequipment 125. As shown, the deployment equipment 125 includes a skid145 for accommodating the drum 130 along with a processing unit 140.Additionally, a line tension detection mechanism 137 and a line lengthdetection mechanism 135, such as an integrated depth wheel (IDW) arealso provided. In the embodiment shown, these mechanisms 135, 137 aresituated at the processing unit 140 so as to interface the well accessline 110 while also coupling to a processor of the processing unit 140.Thus, tension and length information relative to the line 110 may betransmitted to the processor so as to determine load on the drum 130during the operation. This technique for monitoring the load on the drum130 is detailed further below.

Continuing with reference to FIG. 1, the length detection mechanism 135is configured to meter the amount of line 110 that is deployed into andout of the well 180 during an operation such as the depicted loggingoperation. Similarly, the tension detection mechanism 137 may be astrain gauge based device configured to detect the tension on the line110 throughout the operation. With brief added reference to FIG. 3A,these mechanisms directly interface the line 110 so as to pass lineinformation (310, 320) to the processor of the processing unit 140. Inturn, the processor may be pre-loaded with certain drum and linecharacter information that, when analyzed as shown at 330 in light ofthe acquired line information, may ultimately reveal drum load inreal-time over the course of the operation (see 340).

In the embodiment shown, the tension detection mechanism 137 ispositioned near the drum 130. This may serve to approximate the tensionimparted on the drum 130 by the line 110 with significant precision.Indeed, in another embodiment, the tension detection mechanism 137 maybe incorporated into the length detection mechanism 135. Alternatively,a logging head 176 coupled to the line 110 in the well 180 may beequipped with a sensor 175 to serve as a tension detection mechanism. Inyet another embodiment, tension may be measured from multiple locations,including a location associated with a capstan at the surface of theoilfield 297 (see FIG. 2). Whatever the case, the tension detectionmechanism 175 (or mechanisms) may be configured to directly couple tothe line 110 to detect tension, while simultaneously beingcommunicatively coupled to the processor and/or processing unit 140.Such communicative coupling may even be wireless.

As shown in FIG. 1, and alluded to above, logging equipment 160 isdeployed in the well 180 for a logging operation. This may includedeploying the equipment 160 several thousand feet into a formation 195through a well 180. Indeed, in the embodiment shown, the well 180 may beof a deviated character which often adds to the load imparted on thedrum 130 during retrieval of the line 110 as described further below.Additionally, the logging tool 177 may be equipped with diagnosticimplements such as ejector 171 and saturation 173 implements to obtainwater flow information. Additionally, an imaging implement 172 may beprovided as well as a fullbore spinner 170 to measure fluid velocity.

Referring now to FIG. 2, the assembly 100 is shown in the context of alarger overview of an oilfield 297 where logging and other operationsmay take place relative to the well 180. As shown in FIG. 2, the wellaccess line 110 is directed from the drum 130 toward a larger rig 250from which it may be advanced into the well 180. More specifically, theline 110 is strung about lower 252 and upper 255 sheaves and threadedthrough pressure control equipment 257 positioned over the well 180.

From the view of FIG. 2, the tortuous nature of the well 180 isapparent. For example, the well 180 extends vertically through theformation 195 below pressure control equipment 257 at the surface of theoilfield 297. This vertical portion of the well 180 may extend forseveral thousand feet, until reaching a bend 287. At this point, thewell 180 may extend in a deviated or horizontal manner as depicted. Withsuch an architecture, the load imparted by the logging equipment 160 andline 110 may be of concern as the equipment 160 is eventually pulleduphole. That is, while the depth of the well 180 alone may present achallenge to the drum 130 in terms of accommodated load, its tortuousnature may provide even more concern, particularly when it comes topulling the equipment 160 uphole around the bend 287. This may also beof concern when being advanced past the bend 287, for example, throughthe aid of a tractor (not shown).

With such drum load concerns in mind, the assembly 100 is configured toestablish load on the drum 130 in a real-time manner, without solereliance on a pre-set expected load or tension profile. With particularreference to the well 180 and operations in the depicted embodiment,this means that the equipment 160 may be pulled uphole following loggingor in conjunction therewith. As the equipment 160 is pulled uphole,real-time information may be continuously fed to the processing unit140. As indicated above, this information may relate to the tension onthe line 110 (as acquired by the tension detection mechanism 137) aswell as the position or depth of the line 110 (as acquired by the lengthdetection mechanism 135). Thus, given the pre-loaded drum and lineinformation stored on the processor of the processing unit 140, the loadimparted on the drum 130 may be established at all times throughout theoperation.

With real-time drum load information available, evasive or correctiveaction may take place upon approaching a pre-determined drum loadthreshold, also referred to as a maximum bending momentum. So, forexample, depending on the particular type of drum 130 employed, a loadthreshold may be established. The load threshold may be based on amaximum bending momentum in the core/flange junction and on a maximumpressure on the core (discussed in more detail below) and may be definedin terms of force, and may be, but is not limited to, 9,000 lbs or more.In such an embodiment, any real-time detection by the assembly 100 of aload equal to or greater than the load threshold on the drum 130 mayresult in slowing down or shutting off of the uphole advancement of theequipment 160. In the embodiment shown, this may be prone to occur atthe bend 287. However, this is not a certainty, nor is the preciselocation of the bend 287. Nevertheless, the assembly 100 is employed tomake such a determination through direct monitoring in real-time so asto provide a degree of reliability previously unavailable. Thus, theoperator is not limited to what may be gathered from an expected load ortension profile which may be out of date or less than accurate.

Referring now to FIG. 3A, a schematic representation of drum loadmonitoring according to embodiments described above is shown. Namely, aprocessor is employed to run computational analysis as indicated at 330.The analysis is based on information that may be pre-loaded into theprocessor, such as the amount of line on the loaded on the drum and itsexpected tension profile. Other line characteristics such as diameter,stretch profile, and history (i.e. prior usage of the line) maysimilarly be pre-loaded. Additionally, the type of drum in terms ofmaterials and architecture, its dimensions, history and othercharacteristics are also pre-loaded. Once an operation commences,real-time information regarding line length and tension may then be fedto the processor during the operation as noted at 310 and 320. Withthese various types of information on hand, the processor may employconventional algorithmic techniques to establish the load on the drumduring the operation.

As indicated at 340, the load determination may be established inreal-time during an operation. As detailed above, this may allow theoperation to be adjusted or halted altogether in response to a real-timedetermination of the drum load exceeding a predetermined load threshold.Furthermore, the determination of load may include specificallyidentifying the relationship of the load relative to the physicalmorphology of the drum (see 340). That is, as detailed further belowwith reference to FIGS. 4B and 4C, load at particularly impactedlocations of the drum 130 may be established through techniques detailedherein.

Referring now to FIG. 3B, a flow-chart is shown which provides a largeroverview of an embodiment of establishing drum load in real-time. Asindicated at 350, well access line is wound about the drum and druminformation is pre-loaded on a processor of the drum load monitoringassembly (see 355). As noted above, additional information related tocharacteristics of the line may also be pre-loaded on the processoreither before, during, or after the well access line is wound about thedrum including, but not limited to, the expected tension profile of thewell access line. Other pre-loaded information may include, but is notlimited to, maximum number of cycles for the drum and the number ofcycles performed with the drum. Once line and information pre-loading iscompleted, the drum and assembly may be positioned at the oilfield asindicated at 360. As such, the line and operation equipment may bedeployed into a well at the oilfield as indicated at 365.

From the time the line is drawn from the drum, its tension and lengthmay be monitored as indicated at 370 by the drum load monitoringassembly. Thus, real-time data may be fed to the processor from theoutset of operations until the line is retrieved from the well (see380). As a result, real-time load on the drum may be monitoredthroughout operations as indicated at 375. That is, with pre-loadedinformation available relative to drum and line characteristics, theprocessor is able to establish real-time drum load from the dynamic linelength and tension data that is acquired. Therefore, should drum loadconcerns be detected, line positioning may be adjusted as noted at 385.

So, for example, where a real-time load on the drum is detected thatapproaches a pre-determined load threshold for the drum, the positioningof the line may be slowed (e.g. 390) or halted altogether (e.g. 395).This may be more likely to occur during uphole retrieval of the line andother operation equipment (e.g. such as where the equipment rounds abend 287 as depicted in FIG. 2). However, drum load concerns may ariseat any time. For example, where a tractored deployment of equipmentdownhole is utilized, unexpected obstructions and other obstacles mayarise that are prone to increase the load on the drum. When this occurs,it may be safer to slow the rate of line and equipment positioning asnoted at 390 or even to halt the operation altogether as noted at 395.That is, in certain circumstances, even halting operations followed bysubsequent fishing may be more prudent and less costly than risking lossof the drum due to excessive load thereon.

In addition to establishing drum load as noted above, the processor mayprovide additional calculations as a result of having the pre-loaded andreal-time information available. For example, the processor may beemployed to keep track of the number of wraps of the line about the drumas well as the center of each wrap. Calculations may be made regardingtension loss factor and ultimately, a two or three dimensional mappingof the load on the drum 130 may be established. This mapped load mayreveal locations of pressure relative to the core 450, flanges 475 orjunctions 425, 426 of the drum 130 (see FIGS. 4B and 4C).

Referring now to FIG. 4A, a chart is shown which depicts the variationin load imparted on a drum over the course of an operation. Asindicated, the load is a result of tension imparted through a wellaccess line to its associated drum. In the embodiment shown, the drum israted to reliably operate at up to the load threshold. Thus, keeping theload imparted on the drum at below the load threshold may help avoiddrum damage. With brief added reference to FIGS. 4B and 4C, the loadimparted on the drum 130 during the operation of FIG. 4A may be visuallyrepresented with two dimensionally mapped pressure points 400, 410, 411.

Continuing now with reference to FIG. 4A, the chart begins at the leftwith the line disposed in the well for operations similar to that ofFIGS. 1 and 2. Notice the minimal to none ‘line on the drum length’ atthe far left of the x-axis. At this point, the load on the drum is shownas a little over about 7,000 lbs. The chart continues to the right asthe drum is employed to retrieve well access line and increase the ‘lineon the drum length’. With added reference to FIG. 2, this retrieval ofthe line 110 may continue until the equipment 160 reaches the bend 287in the well 180. At this point the load on the drum 130 may spike up abit (as noted at 450). However, as detailed above, the increase in loadis detected in real-time. Thus, to the retrieval speed of the line 110and equipment 160 may also be adjusted at just the right time so as toprevent the load on the drum from spiking above the load threshold (see475) as might otherwise be the case. The remainder of the line 110 maythen be pulled up through the vertical section of the well 180. At thispoint, the line 110 on the drum 130 steadily builds while its loadthereon steadily reduces.

Continuing now with reference to FIGS. 4B and 4C, a side view of thedrum 130 is shown that reveals a map of site specific pressuredistribution of the load resulting from the operation of FIG. 4A.Specifically, the load on the core 450 is shown by vertical pressure 400whereas horizontal pressure 410 is imparted on the flanges 475. Asdepicted, the greater the amount of pressure 400, 410, the larger thecorresponding arrow. For example, notice that the horizontal pressure410 on the flanges 475 is greatest nearer the core 450 and generallyless and less with each successive wrap of line thereabove. In oneembodiment, the core 450 and flange 475 forces may be graphicallypresented to an operator as a matter of user-friendliness. As such, theoperator will be able to monitor the load on different parts of the drum130 at any given moment of the operation. For example, FIGS. 4A and 4Breveal two dimensional mapping with all pressure 400, 410, 411 depictedabove the core 450. However, a three dimensional rendering of pressure400, 410, 411 fully distributed about the core 450 may also begenerated.

Continuing with reference to FIGS. 4A and 4B, the map of pressurereveals a couple of noteworthy pressure revelations. For example,irrespective of load monitoring as described herein, the drum 130 issubjected to the greatest amount of pressure at the junctions 425, 426of the core 450 and flanges 475. This is where the greatest amount ofhorizontal pressure 410 meets up with a generally consistent amount ofvertical pressure 400. Nevertheless, as operations proceed, loadmonitoring may be employed to minimize vertical and horizontal pressurespikes 411 (e.g. as equipment 160 rounds a bend 287 as described aboveand with respect to FIG. 2).

Indeed, as shown in FIGS. 4A and 4B, a fairly precise depiction of thetwo dimensional location of pressure spikes 411 may be provided. Forexample, as depicted, the pressure spikes 411 are imparted on the drum130 by line that is wrapping nearer the left core-flange junction 425 ata few layers up relative to the core 450. As such, a more informativeaccount of the load may be provided. Indeed, as described below, theaccounting of the load may be both more informative and maintained overtime thereby providing a more accurate reflection of the condition ofthe drum 130 throughout its life.

Referring now to FIG. 5 a chart is shown depicting drum history in termsof total load over the course of different well access operations. So,for example, the drum may initially be provided free of any well accessline as indicated at 510 where the total load is 0. The drum may beequipped with line thereabout according to a given tension profile asindicated at 501. As shown at 520, the loaded drum may then be stored orsent to an operation site with a load of under about 9,000 lbs. Duringan operation, line deployment into a well may initially reduce the loadas indicated at 580. However, subsequent retrieval of the line asindicated at 502 is likely to once again increase the imparted load (see540). Similarly, a subsequent deployment of the line in later operationsmay reduce the load as noted at 590. However, the retrieval of the lineas shown at 503 is likely to once again increase the load. Indeed wheresubsequent operations are in a more tortuous well, the retrieval of theline may impart a greater load than before (see 560).

With such a drum load history available as depicted in FIG. 5, theoperator is able to make informed decisions about whether or not toutilize a given previously used drum for a given operation. That is,through conventional tagging, bar-coding, RFID or other identifyingtechniques, the cumulative history of a given drum may be readilybrought up for the operator's review. The data and/or cumulative historyof a given drum may also be stored on a memory device 131, best seen inFIG. 1 attached to the drum 130 (for example with some sort ofnon-volatile memory including, but not limited to, flash memory devicesor the like), as will be appreciated by those skilled in the art. Thememory device 131 may be in communication with or otherwisecommunicatively coupled to the processor and/or processing unit 140.Such communicative coupling may even be wireless. The memory device 131may be at least a source of pre-loaded information stored in memory ofprocessor. Thus, odds are reduced of bypassing or discarding a costlydrum before necessary or accidentally employing a previouslyoverstressed drum. In addition, having defined a maximum number ofcycles that a drum can withstand, the number of logging cycles performedon the drum may be controlled, in order to be able to retire the drumbefore reaching this limit.

Embodiments described hereinabove provide for the establishment of areal-time drum load profile that is actual as opposed to ‘expected’.Thus, the unexpected may be accounted for in real-time and recorded forfuture use. Such actual real-time drum load monitoring is achieved in areliable manner without requiring mechanical interfacing relative to arotating drum during operations. Nevertheless, the load imparted duringoperations may even be roughly mapped in a two or three dimensionalmanner relative to different regions or locations on the drum.

The preceding description has been presented with reference to presentlypreferred embodiments. Persons skilled in the art and technology towhich these embodiments pertain will appreciate that alterations andchanges in the described structures and methods of operation may bepracticed without meaningfully departing from the principle, and scopeof these embodiments. For example, as opposed to wireline, coiled tubingand/or slickline may serve as a well access line for embodiments of loadmonitoring as described herein. Furthermore, the foregoing descriptionshould not be read as pertaining only to the precise structuresdescribed and shown in the accompanying drawings, but rather should beread as consistent with and as support for the following claims, whichare to have their fullest and fairest scope.

1. An assembly for monitoring a load on a drum, the assembly comprising:a line length detection mechanism coupled to a line deployable from thedrum to detect a length of the line relative to the drum; a line tensiondetection mechanism coupled to the line to detect tension on the line;and a processor having pre-loaded drum and line characteristic datastored thereon and coupled to said line detection mechanisms to obtainline length and line tension data therefrom, said processor configuredto run a computation of the pre-loaded data and the obtained line datafor the monitoring.
 2. The assembly of claim 1 wherein the drumcharacteristic data comprises one of drum material, drum architecture,drum dimensions, and drum history.
 3. The assembly of claim 1 whereinthe line characteristic data comprises at least one of an amount of theline on the drum, a tension profile of the line, a diameter of the line,a stretch profile of the line, and line history.
 4. The assembly ofclaim 1 wherein said line tension detection mechanism comprises a straingauge based detector.
 5. The assembly of claim 1 further comprisingdownhole equipment coupled to a downhole end of the well access line. 6.The assembly of claim 5 wherein said line tension detection mechanism isincorporated into one of said line length detection mechanism and saiddownhole equipment.
 7. The assembly of claim 1 wherein the drumcomprises a core to accommodate the line coupled to a flange forretaining the line about the core.
 8. The assembly of claim 7 whereinthe load comprises one of vertical pressure directed at the core andhorizontal pressure directed at the flange.
 9. The assembly of claim 8wherein the computation supports a dimensionally mapped representationof the pressures.
 10. An assembly for delivering downhole equipment to awell at an oilfield, the assembly comprising: a drum for positioning atthe oilfield adjacent the well; a well access line coupled to said drumfor accessing the well with the downhole equipment; a line lengthdetection mechanism for positioning at the oilfield for interfacing saidwell access line to meter an amount thereof in the well; a line tensiondetection mechanism coupled to said well access line to monitor atension thereof; and a processor having a pre-loaded drum and linecharacteristic data stored thereon and coupled to said mechanisms toacquire information relative to the metered amount and the monitoredtension, said processor configured to run a computation of thepre-loaded characteristic data and the acquired information forreal-time monitoring of load on the drum.
 11. The assembly of claim 10wherein said well access line is a wireline cable.
 12. The assembly ofclaim 10 wherein the downhole equipment comprises a logging tool securedto the well access line.
 13. The assembly of claim 10 wherein the wellis of a deviated character.
 14. A method of monitoring a load on a drumaccommodating a line for access to a well, the method comprising:storing pre-loaded drum and line information on a processor, theinformation indicative of physical characteristics of the drum and line;positioning the line within the well; acquiring line information duringsaid positioning, the line information indicative of dynamiccharacteristics of the line; and employing the processor to compute theload on the drum in real-time during said positioning from thepre-loaded information and the acquired information.
 15. The method ofclaim 14 wherein the dynamic characteristics comprise line length andtension.
 16. The method of claim 14 further comprising adjusting a rateof said positioning based on the computed load.
 17. The method of claim14 further comprising halting said positioning based on a computed loadin excess of a predetermined load on the drum.
 18. A method comprising:employing a drum to provide a well access line to a well; monitoring aload on the drum in real-time during said employing; and maintaining aload history of said monitoring.
 19. The method of claim 18 wherein saidmonitoring comprises: storing pre-loaded information on a processorrelative to physical characteristics of the drum and the well accessline; acquiring dynamic information relative to the line during saidemploying; and computing the load in real-time during said employingbased on the pre-loaded information and the dynamic information.
 20. Themethod of claim 18 wherein said maintaining comprises: establishing arecord of the load; and labeling the drum for association with therecord.
 21. The method of claim 18 wherein said maintaining comprises:storing at least the load history on a memory device attached to thedrum.